Filtering composition



2 Sheets-Sheet 1 F. AW. MANNING FILTERING COMPOSITION Filed Aug. '7. 1954 sept. 14, 1937.

SPt- 14, 1937- F. w. MANN|NG 2,093,090

FILTERING COMPOSITION Filed Aug. 7, 1934 2 SheelS-Slfxee'fI 2 Patented Sept. 14, 1937 UNITED STATES FILTERING COMPOSITION Fred W. Manning, Los Angeles, Calif., assignor i6 FredW. Manning Company, Ltd., Los Angeles, Calif., a corporation of California Application August 7,

17 Claims.

This application is a continuation-impart of applications Serial Nos. 588,396 and 684,023, filed by me on January 23, 1932, and August 7, 1933, respectively. My invention relates to the art of removing suspended solids from liquids. It is well adapted to the treatment of lubricating oils, and particularly adapted to the treatment of crankcase oils used in internal combustion engines.

Internal combustion engines are commonly lubricated by oil which is taken from the crankcase and forced by an oil pump to the various parts to be lubricated, the oil then draining back into the crankcase. In the ordinary operation of internal combustion engines, especially when used in motor vehicles, the oil becomes contaminated by filterable matter, such as carbon, road dust, and metal particles abraded from the moving surfaces of the engine. This contamination is so great that it is common practice to periodically remove the contaminated oil from the engine and replace it with clean oil. To lessen the frequency of the oil changes, some motor vehicles are provided with an oil filter through which the oil from the crankcase is continuously circulated while the engine is running for the purpose of removing from the oil the most abrasive of the solid particles.

It has been the practice heretofore to remove lterable impurities from crankcase oils by circulating the oil through sheet material, which is usually a felted or woven fabric. In such fabric filters the lterable material is deposited on the surface of' the fabric and builds up a coating thereon. To prevent rapid clogging, the sheets are made sufficiently porous to allow the finer carbon particles to pass through, and after the sheets have been coated suiiciently with the larger solid impurities to retain the finer ones, the filtrate flow is not rapid enough to remove the finer particles as quickly as formed in the engine. In either case the oil gradually becomes darker in color and finally must be changed. Since such fabric filters, filter almost exclusively at the surface at which the oil enters, and the effective life of the fabric is limited by the coating built up on its surface, the capacity of the filter to remove iilterable matter is directly proportional to the area of its surface.

It is an object of my invention to provide a gel-like material which is produced by the use of fine fibres of animal, vegetable, or mineral origin, and a suitable vehicle; the fibrous material being of such a nature that with the vehicle it will form an adsorption and filtering medium. An exten- 1934, Serial No. 738,789

(Cl. 21o-203) sive filtering medium is thus formed without the necessity of weaving or felting such fibres into a sheet prior to their introduction into the filter. In such a medium theforeign impurities are distributed through its depth rather than on its surface so that its capacity is very nearly proportional to its volume.

It is also an object of my invention to provide a gel-like composition of matter .containing discrete fibres, the composition being of such a nature that under pressure it behaves like most greases in that it will fiow freely and uniformly under pressure without material alteration in its characteristics. This permits the gel-like filtering material being moved by pressure out of a bulk supply space into cheap containers adapted for use in the lubricating systems of internal combustion engines.

In this particular embodiment of my invention I use for a vehicle a moderately viscous lubricaty ing oil at any suitable temperature, those commonly employed for crankcase lubrication being quite suitable. The fibres, such as wood or cotton and asbestos, are intimately and uniformly mixed with a suicient amount of the oil to form a con- 25 sistency characteristic of a fairly stiff gel, which may be then consolidated by expressing a portion of the oil. Other vehicles than oil may be used, provided the vehicle is not deleterious to the liquid to be filtered, or is removed before vthe liquid is about four ounces of such mixture to each quart 4,0

of vehicle Works very well although greater quantities of fibres up to at least six ounces per quart may be used. If cellulose fibres are used alone, even more fibres may be employed.

Increasing the proportion of cellulose fibres to the amount of asbestos fibres used in the gel increases the porosity of the mass when used as a filtering medium, with consequent increase in flow and decrease in clarity of the filtrate.

Hence, of the gel-mass consisting of a fibre mixture suitable for removing all of the finer particles of carbon from crankcase oil, is placed at the end of the filter receptacle adjacent to the oil feed inlet, and a more porous fibre mixture fllls the opposite end of the receptacle, there A mixture of to 35 Vthe same liquid with different fibres.

will result a rapid circulation of the crankcase oil, the oil coming in from the clear filtrate end and passing out at the free flow end with consequent quick heating of the filter and contents, and this will speed up the flow through the clear filtrate section. y

The more or less permanent compacting or consolidating of the fibres in the lter under pump pressure when the gel-mass is put into service, results from the fiow movement of the vehicle against the resistance set up by the fibres to passage of the impurities, the fibres being restrained from free movement by a foraminous filter cake retaining wall. If this resistance is not sufficient t result in the necessary consolidation of fibres to catch all of the impurities during the filtering operation, the resistance can be increased by increasing the filtering pressure. using a finer fibre as by increasing the percentage of asbestos in the gel-mass. and sometimes by decreasing the filtering temperature. 'Ihere is also a repeated expanding and compacting of the fibre mass in the filter resulting from the continual starting and stopping of the engine in a motor vehicle, and this with the constant vibration of the car tends t0 maintain the fibre mass in a porous condition.

To produce this gel-like medium I thoroughly mix the fibres in the liquid in the proportion of two to three ounces per quart of liquid, preferably by feeding the fibres slowly into the vehicle while the latter is kept in agitation; and the fibre content of the gel-mass may be then further increased by expressing a portion of the vehicle during the charging of the gel containers, until the weight of fibre is from four to six ounces per quart of liquid, this preconsolidation of the fibres depending on the filtering pressure to be used. 'I'he higher the filtering pressure, the greater should be the preconsolidation of the fibres in order to maintain as great a volume of fibre filter bed as possible. v But any other means may be used which thoroughly and uniformly disperses and consolidates the fibres in the vehicle and gives a system of interlacing fibres which imparts to the gel-like mass its rigidity. The higher the viscosity of the liquid vehicle the more stiff can the gel mixture be made and still preserve the desired pressuremobile characteristics. Likewise this desired fluidity of the gel under pressure, or during the oil expressing operation, can be increased by increasing the viscosity of the vehicle and sometimes by changing the fibre mixture. The same degree of wetting and adhesion tension against the fibrous material will vary with different liquids of the same viscosity and will also vary for In the case of the gel material herein described, the interfacialtension existing between the fibrous material and the liquid vehicle is such that a high degree of adsorption results at the interface.

By stable gel-like system" I mean a gelatinous product consisting of fibres and of liquid, the product having the characteristics of certain gels and most greases in that it will not flow under normal temperatures except under pressure, and in which the fibres remain in a suspended or dispersed and interlacing condition for 'long periods of time, the rigidity of the gel-like material, and the fixed and uniform distribution of the fibres in the body of it, persisting as the gel is moved from place to place. Most thin liquids as for instance water, gasoline, unconcenerty of forming such a stable gel-like mass with the fibres. The property of forming such a gellike mass depends largely upon the viscosity of the liquid and upon the degree 0f wetting or the adhesion tension of the liquid against the fibres. If cellulose fibres are mixed with a liquid such as water, etc., a gel-like mass is not formed, but a mixture will result from which the water will readily drain, leaving a felted mass of fibres which cannot be made to flow under pressure and which is ineffective for my purpose. A nonclotting or non-matting of the fibres when a small amount of the gel-like material is squeezed between two thin sheets of paper, is an indication that such a mixture can be used as a stable pressure-mobile mass, for in such a case the fibres can be considered as remaining uniformly distributed and unclotted when the mixture is subjected to pressure. It is fairly common knowledge that certain gelatinous materials, and some gels, may be forced through small openings and when forced under high pressure they function as viscous liquids, giving true characteristics of liquid flow. At low pressure this fiow may not be obtained, in which case the pressure is belowr the so-called yield value or zero mobility point.

The majority of true gels are two-phase solidliquid systems. Such gels consist of a network 0f interlacing solid fibrils the spaces between which are permeated by liquid which is held therein by so-called capillary forces. In some cases the solid fibrils may be of ultra-microscopic dimensions and in other cases of microscopic dimensions. In both cases, the fibrils may form gelatinous masses with certain liquids, the liquid being firmly held by the fibre so that the whole mass may be rigid and have the appearance and properties of a. true gel. The product of my invention is of this latter type. In order to avoid the possibility of misunderstanding in the use of terms, my product will be referred to as a pseudo-gel.

Due to the peculiar physical characteristics of my novel separating medium, it is possible to use a very simple form of filter or separator such as that shown in the accompanying drawings, of which,

Fig. 1 is' a vertical section of the filter showing the consolidation of the fibres after use.

Fig. 2 is an elevation of the filter.

Fig. 3 is a plan view of the underside of the cover showing the piercing points.

Fig. 4 is a cross-section on line 4-4 of Fig. 1.

Fig. 5 is a vertical section of an open gel container with the compacting mechanism in position.

Fig. 6 is a cross-section on lines 6-6 of Fig. 5.

Fig. 7 is an elevation of the gel container.

Fig. 8 is a plan view of the gel container.

Referring more specifically to the drawings by reference characters. The filter receptacle I is equipped with agasket 2, and trunnion pins 3 for the saddle 4, which is kept central with the cover by means of the guiding lugs 5. Passing through the central portion of the saddle is an adjusting screw B, the lower spherical end of which is embedded in the cover 1, and the latter is strengthened by the cross ribs 8. 'Ihese ribs also support the piercing points 9, which encircle the feed openings I0. 'I'he receptacle has a fluid inlet II, and a filtrate outlet I2; and inserted on the inside of the latter is a. tube I3, which has openings I4 in its lower end. The

-thimble point.

tube supports a piercing point Il, which may have two or more cutting edges; and between the piercing point and the recessed boss I6 of the receptacle, is a foraminous tubular plate or screen I1; the foraminous member, piercing point, and supporting tube, forming the filtrate thimble of the filter. 'Ihe receptacle is also equipped with a cork gasket I8, and patches I9, for supporting the container, and ribs 20 for centralizing the container.

'I'he gel container, which may be of tin, paper or other suitable material, consists of a shell 2|, cover 22, lifting ring 23, bracket 24, and the clear filtrate and free flow gels 25 and 26, respectively. A compacting device for charging the gel into the container consists of a sleeve 21, spa^ing wire 28, foraminous member 29. the plunger 30, and outlet 3l.

The operation of the apparatus thus constructed has been in part indicated in connection with the foregoing description. VUpon unscrewing the adjusting screw and giving the saddle a slight turn in the proper direction, both cover and saddle `may be lifted entirely from the filter receptacle; and by means of the ring 23 the contaminated gel container may be lifted out and discarded. As the piercing point I5 of the filtrate thimble is a little below the top of the receptacle, a new container may be partly inserted before its bottom will rest on the The container can then be thrust down over the thimble, the point, or cutting edges of the point, easily piercing the bottom of the container, and the displaced gel liquid passing into and out through the thimble. 'I'he saddle can then be swung into position, its outer ends engaging with the trunnion pins 3. This places the cover I in a central position where it is sufficiently adjustable Aby virtue of its spherical connection with the adjusting screw, to find its seat; and the screwing down of the cover will cause the piercing points to enter the top of the container near its circumference, the cork gasket I8 making the joint between the bottom of the container and the recessed boss I6. The fluid to be filtered, after passing through the inlet opening II, will distribute itself around the container, which is maintained in a central position by the ribs 20; and will then pass into the containerthrough the openings Ili in the piercing points 9 that have been thrust through the cover of the container. As the gel is mobile under pressure, the pressure of the incoming fluid Will be exerted throughout the container, and will displace the gel liquid, which passes out through the filtrate thimble, the gel solids also moving towards the thimble as clogging of the fibres occurs, as indicated by the outline of the solids in Fig. 1.

If the gel containers are filled by hand, or with the ordinary can filling machines, the fibre content of the gel-mass will usually be from two to three ounces to each quart of vehicle, the amount 0f fibre incorporated in the vehicle depending on the stiffness to which it is mixed. Such a mixture placed in a filter receptacle will give satisfactory results for many purposes but the fibre content may not be sufficient if the mixture is to be used in the lubricating system of a motor car. The vibrations of the car and the constant varying lubrication pressure, due to starting and stopping of the engine, will ultimately result in sagging of the fibre cake; and the ordinary lubricating pressure of motor cars will result in too much deadl space in the container, due to the consolidation'of the fibres around the filtrate thimble.- To avoid these undesirable results, I

increase the fibre content of the gel-mass in the charging operation to from four to six ounces per quart of vehicle by means of a compacting device, such as is described in Fig. 5. This device may be inserted within the container either before ci* after the former has been filled 'with the requ site amount of gel-mass, and the downward movement of the plunger l0 will cause the oil in the gel-mass'to be expressed through the foramlnous member 29, upward around the spacing wire 28, and through the outlet II The compacting cylinder can then be withdrawn, after which the plunger may be raised and the container capped. In actual practice where a great number of containers are to be filled per hour, it is probable that the compacting cylinder would be filled and the gel-mass consolidated to the desired extent in one movement of the filling machine, and the resulting plug or mass of rfibres shoved out of the compacting cylinder into its container in a second movement of the filling machine; and as a further precaution against 'drippings wetting the outside of the container, the latter may be placed in an upside down position for charging purposes and then automatically righted and capped. Increasing the fibre content within reasonable limits does not alter the characteristics of the gel except to increase the pressure at which it becomes mobile; but the fibre content must not be increased to a point where the film of oil is completely squeezed from between the individual fibres, otherwise the fibre mass ceases to be a pressure-mobile suspension.

It will be obvious from the foregoing description that if a fibrous material is to be used for the purifying of a crankcase oil, it should be introduced directly into the filter. If it is introduced in the form of dry fibres, the spacing of the individual fibres cannot be accomplished uniformly, or discretely, and consequently the passage of oil through a mass of such fibres will never result in a pressure-mobile suspension. If it is mixed with an oil and introduced as a flowable mixture, as is often done in refining operations, there will not be sufficient flow of a clean oil through the comparatively small pipe lines of the lubricating system to consolidate the fibres sufficiently to make-the mixture mobile only under pressure; and as soon as sufficient carbon has been carried into the filter to cause the fibre mass to be no longer iiowable under atmospheric pressure, it will at the same time cease to be mobile under pressure; and the consolidation of the fibre mass will be such that the capacity of the filter has been greatly reduced, this capacity being nearly proportional to the volume of the fibre mass. Moreover, in a compressible filter bed built up by the fibres being carried into position by the flow of the liquid being filtered under a substantially constant maximum pressure, the consolidation of the fibres increases directly with the depth ofthe bed. This is due to the pres'- sure to be supported by the fibres in each successive layer, as they are built up, becoming less as the depth increases, because the pressure across the layer is in ratio of its thickness to the total thickness of the filter bed. When the cake is thin, at the start, the first layer will have to bear nearly the whole of the pressure and afterwards much less. As the depth of the bed increases the later fibres are not submitted to so great an unbalanced pressure as were the earlier fibres,

and are consequently laid down in a more open structure. See Filtration and Filters by J. A. Pickard. Therefore, to obtain the greatest possible capacity for the filter, suitable fibres must not only be uniformly and discretely spaced, but the fibre mass must be introduced into the filter as a preconsolidated pressure-mobile suspension with a sufficient fibre content to retain all impurities without further consolidation of the fibres during use, altho under normal operating conditions a slight further consolidation will occur which will be suicient to permit free circulation of the oil around the filter bed. In other words, preconsolidation of the fibres will prevent later consolidation of the fibres during the ltering operation with consequent loss of filtering capacity. The` filtering pressures of lubricating systems of motor cars usually vary from five to fifty pounds per square inch, and for such pressures four to six ounces of fibres per quart of oil will be found most serviceable. The higher the filtering pressure, the greater should be the preconsolidation of the fibres in the gel-mass;

' and the greater the preconsolidation of the latter,

the less the amount of finer fibre, such as asbestos, that would be required, usually 15 to 20% being suiiicient for normal lubrication pressures and corresponding preconsolidations of the gelmass. Two or more pressure-mobile suspensions containing different kinds, or consolidations, of fibres may function adjacent to one another, as the clear filtrate and free fiow gels 25 and 26, respectively, shown in Fig. 1, or the concentric gels 23, 24, and 25, shown in Figs. l to 4 of my copending application Ser. No. 684,023, filed August i, 1933.

It will also be evident that a gel mixture may be used to filter fuel oils, such as gasoline, in the feed lines of internal combustion engines; and that the gel-mass may be charged into almost any of the usual types of gasoline filters, the oil vehicle being washed out into the` cylinders and replaced in the fibre mass by gasoline during operation of the engine.

It will still further be evident that the piercing points for the container may be placed in the cover, as shown, or in the bottom of the receptacle, or even in the sides of the receptacle if the container is tapered; or the container may be dispensed with entirely, and the gel introduced directly into the receptacle, and upon exhausting of the gel the entire receptacle replaced.

It will be understood throughout the specification and appended claims that a pseudo-gel is a pressure-mobile suspension in which the fibres are uniformly dispersed in a discrete condition throughout the vehicle and unbonded to the extent that they are capable of flow under pressure Without the addition of a liquid and therefore cannot be considered as forming a unitary felti like mass.

I claim as my invention:

l. A filter element comprising fibres uniformly dispersed in a discrete condition throughout a liquid to form a pressure mobile stable gel-like filtering mass throughout which mass the said fibres remain uniformly distributed during the filtering operation.

2. A filter element comprising cellulosic fibres uniformly dispersed in a discrete condition throughout a liquid to form a pressure mobile stable gel-like filtering mass throughout which mass the said fibres remain uniformly distributed during the filtering operation.

dispersed in a discrete condition throughout an oil, such as is used in the lubricating systems of internal combustion engines, to form a pressure mobile stable gel-like filtering mass throughout which mass the said fibres remain uniformly distributed during the filtering operation.

6. A filter element comprising fibres uniformly dispersed in a discrete condition throughout a liquid to form a pressure mobile stable gel-like filtering mass containing from four to six ounces of fibres for each quart of liquid, the said fibres remaining uniformly distributed throughout the said mass during the filtering operation.

7. A filter element comprising fibres uniformly dispersed in a discrete condition throughout an oil, such as is used in the lubricating systems of internal combustion engines, to form a pressure mobile stable gel-like filtering mass containing from four to six ounces of fibres for each quart of oil, the said fibres remaining uniformly distributed throughout the said mass during the illtering operation.

8. A filter element comprising asbestos fibres in mixture with a preponderant proportion of cellulosic fibres and both of said fibres uniformly dispersed in a discrete condition throughout a liquid to form a pressure mobile stable gel-like filtering mass throughout which mass the said fibres remain uniformly distributed during the filtering operation.

9. A lter element comprising asbestos fibres in `mixture with a preponderant proportion of cellulosic fibres and both of said fibres uniformly dispersed in a discrete condition throughout an oil, such as is used in the lubricating systems of internal combustion engines, to form a pressure mobile stable gel-like filtering mass throughout which mass the said fibres remain uniformly distributed during the filtering operation.

10. A method of forming a filter element comprising uniformly dispersing fibre dust in a discrete condition throughout a liquid to form apressure mobile stable gel-like filtering mass throughout which mass the said fibres remain uniformly distributed during the filtering operation.

11. A method of forming a filter element comprising: uniformly dispersing fibres in a discrete condition throughout a liquid to form a pressure mobile stable gel-like filtering mass; and removing a portion of the liquid therefrom, the fibres remaining uniformly distributed throughout the said mass during the said removing and also the filtering operation.

12. A method of forming a filter element comprising: uniformly 4dispersing fibres in a discrete condition throughout an oil, such as is used in the lubricating systems of internal combustion engines, to form a pressure mobile stable gel-like filtering mass; and removing a portion of the oil therefrom, the fibres remaining uniformly disdate the said fibres in the said mass, the fibres remaining uniformly distributed throughout the 10 said mass during the consolidating and filtering operations.

14. A method of forming a lter element comprising: uniformly dispersing bres in a discrete condition throughout an oil, suclias is used in 15 the lubricating systems of internal combustion engines, to form a pressure mobile stable gellike ltering mass; and removing a portion of the oil therefrom to consolidate the said fibres in the said mass, the fibres remaining uniformly dis- 20 tributed throughout the said mass during the consolidating and filtering operations.

15. A method of forming a filter element comprising: uniformly dispersing fibres in a discrete condition throughout a liquid to form a pressure 2E mobile stable gel-like mass; and removing a portion of the-liquid therefrom until a consolidated filtering mass is formed lcontaining from four to six ounces of fibres for each quart of liquid,

the bres remaining uniformly distributed throughout the said mass duringthe consolidating and filtering operations. A

16. A method of forming a. lter element comprising: uniformly dispersing fibres in a discrete condition throughout an oil, such as is used in.

the lubricating systems of internal combustion engines, to form a pressure mobile stable gel-like mass; and removing a portion of the oil therel from until a consolidated filtering mass is formed containing from four to six ounces of fibres for each quart of oil, the bres'remaining uniformly distributed throughout the said mass during the consolidating and filtering operations.

17. A method of forming a filter element comprising: uniformly dispersing fibres in a discrete condition throughout an oil; such as is used in the lubricating systems of internal combustion engines, in the proportion' of two to three ounces of bres to each quart of oil, to form a pressure mobile stable gel-like mass; removing a portion of the oil therefrom until a consolidated filtering mass is formed containing from four to six ounces of bres for each quart of oil, the fibres remaining uniformly distributed throughout the said mass during the consolidating and filtering operations.

FRED W. MANNING.V 

